U.S. patent number 5,692,689 [Application Number 08/658,709] was granted by the patent office on 1997-12-02 for cutter device and method for cleaning and mulching trees.
Invention is credited to Rickey D. Shinn.
United States Patent |
5,692,689 |
Shinn |
December 2, 1997 |
Cutter device and method for cleaning and mulching trees
Abstract
A cutter device is provided for being attached to an end of a
movable working arm of a self-propelled vehicle for clearing and
mulching trees. The cutter device includes a rotatably mounted drum
with a plurality of spaced cutter teeth attached to an exterior of
the drum for engaging and grinding the trees. A shield covers a
portion of the drum and contains the deflection of wood debris
outwardly from the drum during operation. The shield has an
interior wall spaced apart from the cutter teeth and cooperating
with the rotating drum to define a debris flow path through the
device. At least one deflector plate is attached to the interior
wall of the shield. The deflector plate extends inwardly into the
debris flow path in a direction towards the cutter teeth of the
drum. The interior wall of the shield and the deflector plate
collectively form a mulch zone in an area between the cutter teeth
and the shield and upstream of the deflector plate for slowing the
movement of debris along the flow path, and deflecting the debris
back into contact with the cutter teeth for being further cut and
reduced in size.
Inventors: |
Shinn; Rickey D. (Concord,
NC) |
Family
ID: |
24642349 |
Appl.
No.: |
08/658,709 |
Filed: |
June 5, 1996 |
Current U.S.
Class: |
241/101.72;
144/24.12; 144/334; 241/101.74; 241/285.1 |
Current CPC
Class: |
A01G
23/067 (20130101); A01G 23/093 (20130101) |
Current International
Class: |
A01G
23/093 (20060101); A01G 23/00 (20060101); A01G
23/06 (20060101); B02C 013/04 (); A01G
023/08 () |
Field of
Search: |
;241/101.72,101.74,101.742,82,273.3,285.1,185.5,186.2
;144/375,24.12,34.1,334 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Howell; Daniel W.
Assistant Examiner: Krolikowski; Julie A.
Attorney, Agent or Firm: Adams Law Firm, P.A.
Claims
I claim:
1. A cutter device for being attached to an end of a movable
working arm of a self-propelled vehicle for clearing and mulching
trees, said cutter device comprising:
(a) a rotatably-mounted drum;
(b) a plurality of spaced cutter teeth attached to an
axially-extending peripheral surface of said drum for engaging and
grinding trees;
(c) a shield covering a portion of said drum, and comprising a
substantially flat top wall and substantially flat front and rear
side wails attached to the top wall for containing the deflection
of wood debris outwardly from said drum during operation, and the
walls of said shield collectively defining an interior surface
spaced apart from said cutter teeth and cooperating with said
rotating drum to define a debris flow path through the device;
(d) at least one deflector plate attached to at least one of the
top and rear side walls on the interior surface of said shield, and
extending inwardly into the debris flow path at an angle of greater
than 90 degrees to the wall which it is attached, and along a
notional line generally tangent to the peripheral surface of said
drum; and
(e) said deflector plate and the interior surface of said shield
adjacent to and upstream of said deflector plate cooperating to
form a mulch zone in an area between the cutter teeth and said
shield for slowing the movement of debris along the flow path, and
deflecting the debris back into contact with said cutter teeth for
being further cut and reduced in size.
2. A cutter device according to claim 1, wherein the interior angle
formed between the front side wall and the top wall of said shield
is between 110 and 130 degrees.
3. A cutter device according to claim 1, wherein the interior angle
formed between the rear side wall and the top wall of said shield
is between 110 and 130 degrees.
4. A cutter device according to claim 1, wherein said deflector
plate is attached to the top wall of said shield.
5. A cutter device according to claim 4, wherein said deflector
plate extends from the top wall at an angle substantially
perpendicular to the front side wall of said shield.
6. A cutter device according to claim 1, and comprising a second
deflector plate attached to the rear side wall of said shield, and
defining a second mulch zone downstream of said first mulch zone
for further slowing and deflecting debris back into contact with
said cutter teeth.
7. A cutter device according to claim 6, wherein said second
deflector plate extends from the rear side wall at an angle
substantially perpendicular to the top wall of said shield.
8. A cutter device according to claim 1, wherein said shield
further comprises substantially flat, front and rear end walls
attached to respective front and rear side walls for covering a
front and rear portion of the drum.
9. A cutter device according to claim 8, wherein the front end wall
extends at an angle of between 120 and 140 degrees relative to the
front side wall of said shield.
10. A cutter device according to claim 1, wherein the rear end wall
extends at an angle of between 120 and 140 degrees relative to the
rear side wall of said shield.
11. A cutter device according to claim 1, wherein said cutter teeth
are arranged in a plurality of rows spaced apart around the
circumference of said drum.
12. A cutter device according to claim 11, wherein adjacent ones of
said rows are off-set to increase contact between the cutter teeth
and the debris as the debris moves along said flow path.
13. A cutter device according to claim 1, and comprising an
outwardly extending rake attached to a rear portion of said shield
for being maneuvered by the working arm of the vehicle to clear
sections of cut trees from the path of the vehicle.
14. In combination with a self-propelled vehicle having a movable
working arm, a cutter device attached to an end of the working arm
for rearing and mulching trees, said cutter device comprising:
(a) a rotatably-mounted drum;
(b) a plurality of spaced cutter teeth attached to an
axially-extending peripheral surface of said drum for engaging and
grinding trees;
(c) a shield covering a portion of said drum and comprising a
substantially flat top wall and substantially flat front and rear
side walls attached to the top wall for containing the deflection
of wood debris outwardly from said drum during operation, and the
walls of said shield collectively defining an interior surface
spaced apart from said cutter teeth and cooperating with said
rotating drum to define a debris flow path through the device;
(d) at least one deflector plate attached to at least one of the
top add rear side walls on the interior surface of said shield, and
extending inwardly into the debris flow path at an angle of greater
than 90 degrees to the wall which it is attached and along a
notional line generally tangent to the peripheral surface of said
drum; and
(e) said deflector plate and the interior surface of said shield
adjacent to and upstream of said deflector plate cooperating to
form a mulch zone in an area between the cutter teeth and said
shield for slowing the movement of debris along the flow path, and
deflecting the debris back into contact with said cutter teeth for
being further cut and reduced in size.
15. A method of clearing and mulching trees, comprising the steps
of:
(a) attaching a cutter device to an end of a movable working arm of
a self-propelled vehicle, said cutter device comprising a rotatably
mounted drum with a plurality of spaced cutter teeth attached to an
axially-extending peripheral surface of the drum for engaging and
grinding the trees, and a shield covering a portion of said drum,
and comprising a substantially flat top wall and substantially flat
front and rear side walls attached to the top wall for containing
the deflection of wood debris outwardly from said drum during
operation;
(b) creating a debris flow path through the cutter device and
between an interior surface of said shield and the cutter teeth of
said rotating drum;
(c) attaching at least one deflector plate to at least one of the
top and rear side walls on the interior surface of said shield,
said deflector plate extending inwardly into the debris flow path
at an angle of greater than 90 degrees to the wall which it is
attached, and along a notional line generally tangent to the
peripheral surface of said drum; and
(d) as the debris moves along said flow path, deflecting the debris
away from the interior surface of said shield and back into contact
with said cutter teeth for being further cut and reduced in size.
Description
TECHNICAL FIELD AND BACKGROUND OF THE INVENTION
This invention relates to a cutter device and method for clearing
and mulching trees. The invention is mounted on the working arm of
a self-propelled vehicle, such as a backhoe, and is particularly
applicable for clearing large areas of land for construction
projects, such as the installation of underground piping or above
ground construction. Complete clearing of trees, stumps, and brush
is accomplished relatively quickly and in a safe and efficient
manner.
When cutting trees, the invention creates a fine wood mulch of
substantially uniform size and dimension. Due to the small size of
the mulch, there is less danger of being injured by debris
deflecting outwardly from the cutter device during operation.
Moreover, the invention may be readily adapted to provide for
automatic collection and recycling of the debris for use in
landscaping, particle board construction, or for other
purposes.
One prior art cutter device is disclosed in U.S. Pat. No.
5,499,771. This device includes a rotating cutter drum and a
semi-cylindrical shield which covers a portion of the drum for
containing the deflection of wood debris outwardly from the drum
during operation. The device aims to reduce the size of wood debris
exiting from beneath the shield by positioning the shield at a
constant radial distance from the cutter drum.
As compared to the present invention, the cutter device of '771
patent has proven to be inadequate. The prior art device creates
relatively large and long strips of wood debris which are generally
not desirable for collection and recycling, and which increase the
potential for injury to nearby workers during operation. The air
flow generated by the rotating cutter drum moves the debris along a
flow path closely adjacent to the inner wall of the shield away
from the teeth of the drum. Thus, once an initial cut is made, the
debris is exposed to relatively little contact with the drum teeth
before being exhausted outwardly from beneath the shield. These
generally long strips of debris not only increase the potential for
injury, but may also interfere with proper operation and efficiency
of the rotating cutter drum.
SUMMARY OF THE INVENTION
Therefore, it is an object of the invention to provide a cutter
device for being mounted on the working arm of a backhoe for
clearing and mulching trees.
It is another object of the invention to provide a cutter device
with reduced danger of injury from deflecting debris during
operation.
It is another object of the invention to provide a cutter device
which slows the flow of debris through the device, and causes
increased contact between the debris and cutter teeth of the
rotating drum as the debris passes beneath the shield.
It is another object of the invention to provide a cutter device
which creates a relatively fine mulch suitable for collection and
reuse in landscaping.
It is another object of the invention to provide a cutter device
which creates a mulch of relatively uniform size and dimension.
These and other objects of the present invention are achieved in
the preferred embodiments disclosed below by providing a cutter
device for being attached to an end of a movable working arm of a
self-propelled vehicle for clearing and mulching trees. The cutter
device includes a rotatably mounted drum with a plurality of spaced
cutter teeth attached to an exterior of the drum for engaging and
grinding the trees. A shield covers a portion of the drum and
contains the deflection of wood debris outwardly from the drum
during operation. The shield has an interior wall spaced apart from
the cutter teeth and cooperating with the rotating drum to define a
debris flow path through the device.
At least one deflector plate is attached to the interior wall of
the shield. The deflector plate extends inwardly into the debris
flow path in a direction towards the cutter teeth of the drum. The
interior wall of the shield and the deflector plate collectively
form a mulch zone in an area between the cutter teeth and the
shield and upstream of the deflector plate for slowing the movement
of debris along the flow path, and deflecting the debris back into
contact with the cutter teeth for being further cut and reduced in
size.
According to one preferred embodiment of the invention, the shield
includes a substantially flat top wall, and substantially flat
front and rear side walls attached to the top wall. The front and
rear side walls extend at respective obtuse angles relative to the
top wall, and together with the top wall, collectively cover an
upper portion of the drum.
Preferably, the interior angle formed between the front side wall
and the top wall of the shield is between 110 and 130 degrees.
Preferably, the interior angle formed between the rear side wall
and the top wall of the shield is between 110 and 130 degrees.
According to another preferred embodiment of the invention, the
deflector plate is attached to the top wall of the shield.
According to yet another preferred embodiment of the invention, the
deflector plate extends from the top wall at an angle substantially
perpendicular to the front side wall of said shield.
According to yet another preferred embodiment of the invention, a
second deflector plate is attached to the rear side wall of the
shield, and defines a second mulch zone downstream of the first
mulch zone for further slowing and deflecting debris back into
contact with the cutter teeth.
According to yet another preferred embodiment of the invention, the
second deflector plate extends from the rear side wall at an angle
substantially perpendicular to the top wall of the shield.
According to yet another preferred embodiment of the invention, the
shield further includes substantially flat, front and rear end
walls attached to respective from and rear side walls for covering
a front and rear portion of the drum.
Preferably, the front end wall extends at an angle of between 120
and 140 degrees relative to the from side wall of the shield.
Preferably, the rear end wall extends at an angle of between 120
and 140 degrees relative to the rear side wall of the shield.
According to another preferred embodiment of the invention, the
cutter teeth are arranged in a plurality of rows spaced apart
around the circumference of the drum.
According to yet another preferred embodiment of the invention,
adjacent ones of the rows are off-set to increase contact between
the cutter teeth and the debris as the debris moves along the flow
path.
According to yet another preferred embodiment of the invention, an
outwardly extending rake is attached to a rear portion of the
shield for being maneuvered by the working arm of the vehicle to
clear sections of cut trees from the path of the vehicle.
An embodiment of the method according to the invention comprises
the steps of attaching a cutter device to an end of a movable,
working arm of a self-propelled vehicle. The cutter device includes
a rotatably mounted drum with a plurality of spaced cutter teeth
attached to an exterior of the drum for engaging and grinding the
trees. A shield covers a portion of the drum and contains the
deflection of wood debris outwardly from the drum during
operation.
A debris flow path is created through the cutter device and between
an interior wall of the shield and the cutter teeth of the rotating
drum. As the debris moves along the flow path, it is deflected away
from the interior wall of the shield and back into contact with the
cutter teeth for being further cut and reduced in size.
BRIEF DESCRIPTION OF THE DRAWINGS
Some of the objects of the invention have been set forth above.
Other objects and advantages of the invention will appear as the
description proceeds when taken in conjunction with the following
drawings, in which:
FIG. 1 is an environmental perspective view of a backhoe with an
attached cutter device according to one preferred embodiment of the
invention;
FIG. 2 is a side perspective view of the cutter device as attached
to the working arm of the backhoe, and showing the cover plate and
pulley cap removed;
FIG. 3 is an opposite side perspective view of the cutter device as
attached to the working arm of the backhoe;
FIG. 4 is a side elevational view of the cutter device;
FIG. 5 is an opposite side elevational view of the cutter
device;
FIG. 6 is a fragmentary, cross-sectional view of the cutter device
showing the flow of wood debris through the device; and
FIG. 7 is a bottom plan view of the cutter device showing the
arrangement of cutter teeth on the exterior of the drum.
DESCRIPTION OF THE PREFERRED EMBODIMENT AND BEST MODE
Referring now specifically to the drawings, a cutter device
according to the present invention is illustrated in FIG. 1 and
shown generally at reference numeral 10. The cutter device 10 is
adapted for being mounted on the working arm 11 of a self-propelled
vehicle, such as a backhoe 12, and is particularly applicable for
clearing large areas of land to facilitate installation of
underground piping or above ground construction.
As is best shown in FIGS. 2-5, the cutter device 10 includes a
shield 15 with attached front and rear mounting feet 16 and 17 for
securing the cutter device 10 to the arm 11 of the backhoe 12. A
drum 18 is rotatably mounted beneath the shield 15, and includes a
number of outward-extending teeth 21 for engaging and grinding
trees. The shield 15 covers an upper portion of the drum 18 to
contain the deflection of debris outwardly from the cutter device
10 during operation, and to increase the cutting of debris to form
a mulch of relatively small, uniform size.
The drum 18 is carried by an elongated drive shaft 22, and actuated
by one or more belts 24 and pulleys 25 connected to the drive shaft
22 and a hydraulic motor "M". The drive shaft 22 is supported at
opposite ends by support plates 26 and 27 mounted to the interior
of the shield 15. According to one embodiment, the drum 18 is 24
inches in diameter and rotates at between 850-1500 rpm.
Preferably, circular end caps 28 and 29 are located on opposite
open ends of the drum 18 adjacent to respective support plates 26
and 27 to prevent debris from entering the drum 18 and interfering
with operation of the drive shaft 22. The end caps 28 and 29 are
secured to the support plates 26 and 27, and include respective
bearing joints (not shown) engaging the shaft 22 to reduce the loss
of energy through friction. Top and side covers 31 and 32 are
preferably attached to the shield 15 for protecting the belt 24 and
pulley 25 against damage when operating the cutter device 10. In
addition, an outwardly-extending rake 33 is attached to the rear
mounting foot 17 on the arm 11 of the backhoe 12, and is maneuvered
by the backhoe operator to clear sections of cut trees from the
path of the backhoe 12.
Construction and Operation of the Shield 15
Referring to FIG. 6, the shield 15 includes a top wall 35, front
and rear side walls 36 and 37 attached to the top wall 35, and
front and rear end walls 38 and 39 attached to respective front and
rear side walls 36 and 37. The walls 35-39 are substantially flat,
and are attached together by welding or other suitable means. The
interior angle defined by each of the front and rear side walls 36
and 37 relative to the top wall 35 is about 110-130 degrees. The
angle defined by each of the front and rear end walls 38 and 39
relative to the front and rear side walls 36 and 37, respectively,
is about 120-140 degrees.
The walls 35-39 of the shield 15 are spaced-apart from the teeth 21
of the drum 18, and cooperate with the drum 18 when rotating to
create a debris flow path through the cutter device 10. As the
teeth 21 engage the tree for cutting, relatively large pieces of
wood debris "D" enter an area beneath the shield 15 and are moved
downstream along the flow path to a first mulch zone 40 formed at
the junction of the front side wall 36 and top wall 35. The mulch
zone 40 is an enlarged open area defined by portions of the front
side wall 36 and top wall 35, and an angled deflector plate 41
attached to the top wall 35. The deflector plate 41 preferably
extends the entire length of the shield 15, and projects inwardly
about 1-2 inches towards the teeth 21 at an angle of about 90
degrees relative to the front side wall 36, and preferably along a
notional line generally tangent to the peripheral surface of the
drum 18. The deflector plate 41 and walls 35, 36 cooperate to slow
the movement of debris "D" along the flow path, and to deflect the
debris "D" back into contact with the teeth 21 for further
cutting.
From the first mulch zone 40, the debris "D" moves further
downstream along the flow path to a second mulch zone 50 formed at
the junction of the top wall 35 and rear side wall 37. The second
mulch zone 50 is a second enlarged open area defined by portions of
the top wall 35 and rear side wall 37, and a second deflector plate
51 attached to the rear side wall 37. The deflector plate 51
preferably extends the entire length of the shield 15, and projects
inwardly about 1-2 inches towards the teeth 21 at an angle of about
90 degrees relative to the top wall 35, and preferably along a
notional line generally tangent to the peripheral surface of the
drum 18. The deflector plate 51 and walls 35, 37 cooperate to slow
the movement of debris "D" along the flow path, and to deflect the
debris "D" back into contact with the teeth 21 for further cutting.
The debris "D" exiting the cutter device 10 downstream of the
second mulch zone 50 is a relatively fine mulch of generally
uniform size and dimension.
In addition to the mulch zones 40 and 50 described above, the
particular arrangement of teeth 21 on the drum 18 promotes further
cutting of debris, and causes increased air flow through the cutter
device 10. As shown in FIGS. 6 and 7, each tooth 21 is carried by a
holder 21A and includes a reinforced backing 21B to strengthen the
attachment of the tooth 21 to the drum 18. The holders 21A are
approximately 3.0 inches wide and 1.5 inches tall, respectively,
and are attached to the outer drum surface by welding. The teeth 21
are spaced apart in rows "R" of 6-8 along the circumference of the
drum 21 with adjacent rows "R" being slightly off-set from one
another to increase the total number of teeth 21 contacting the
debris as it moves through the cutter device 10. The holders 21A of
two adjacent rows "R" collectively span substantially the entire
length of the drum 18, thereby increasing the overall amount of air
drawn into the flow path beneath the shield 15 during rotation of
the drum 18. Preferably, the air flows through the cutter device 10
at about 100-135 cfm.
In an alternative embodiment (not shown), the cutter device has a
vacuum system including a length of hollow, flexible conduit
communicating with the interior of the shield downstream of the
second mulch zone for collecting the mulch as it exits the shield.
The conduit extends from the shield to a collection basket attached
to the backhoe for storing the mulch.
A cutter device is described above. Various details of the
invention may be changed without departing from its scope.
Furthermore, the foregoing description of the preferred embodiment
of the invention and the best mode for practicing the invention are
provided for the purpose of illustration only and not for the
purpose of limitation--the invention being defined by the
claims.
* * * * *